1. Field of the Invention
This invention relates to cargo carrying containers that are mounted to chassis, as for intermodal transportation and, more particularly, to a cargo carrying container that can be interfaced with chassis having different configurations.
2. Background Art
Throughout North America, there are currently three basic designs that make up a category known as North American Domestic Containers. These containers differ from the more common International Organization for Standardization (ISO) Marine Containers in that they are typically longer, wider, and higher. They are also not intended for ocean-going service and thus the design thereof is required to meet overall strength specifications set up by the Association of American Railroads (AAR) in Specification M-930.
One of the three container designs, considered to be “standard”, utilizes the same basic securement and interface features that are used on the ISO Marine Containers. In this design, spaced apertures are provided on the lower front wall on the container to each receive a rearwardly projecting lock pin on the chassis. At the rear, underside of the container, spaced apertures are provided as part of twist lock securement mechanisms. The aperture pairs, at the front and rear locations, are spaced widthwise on 89 inch centers.
Tunnels are provided on these standard containers to accommodate a forward gooseneck on the chassis. The standard tunnel has a 40.5 inch width and a fore-and-aft length of at least 123 inches. The height of the tunnel is 4.75 inches.
By reason of utilizing the ISO Marine Containers interface features, chassis construction can be standardized. These chassis are commonly used by many different operators for general transport and handling by railroads.
A second of the three container designs is similar to the above, “standard” design, except that it is considered a “High-Cube” design. This design typically is 53 feet in length with a reduced tunnel height of 3.625 inches, as compared to the standard 4.75 inches. This allows for a greater inside cargo space height, which matches and competes with more conventional over-the-road semi-trailer units.
This second design requires a special chassis with a reduced-height gooseneck. The remainder of the interfacing is the same as on the standard unit. This allows for some chassis designs, which provide adaptors on the front of the unit, to accept for transportation either the High-Cube design or the standard tunnel height design.
The third design is one that is a more recent development made by an operator with the intent of limiting the use of that individual's containers and chassis to his own operation, while preventing use by any other operator. To accomplish this, the front and rear apertures were changed from the ISO 89 inch center spacing to a spacing of 92.75 inches. Additionally, the width of the tunnel was reduced from 40.5 inches to 32 inches. These changes prevented any intermixing of that operator's containers and chassis with any other operator's units that were designed around the standard.
While this concept effectively controls equipment usage, it has the drawback that the equipment, by reason of its customized configuration, has a reduced resale value. A further drawback is an increase in the acquisition and/or leasing costs as a result of the likely lower anticipated resale value.
It is known in this industry to oversize apertures to allow a single container to adapt to/interface with chassis having different configurations in terms of the center spacing of the front lock pins and rear twist lock hardware. However, as explained in greater detail below, enlarging component receiving apertures, to provide a universal container configuration, may compromise connection between the container and chassis that may cause damage to one or both of these components or, in a worst case, lead to a dangerous condition of partial or full separation of the container from the chassis.
It is also known to adapt a standard tunnel to a non-standard/modified gooseneck, that is narrower in width. In the absence of some modification, the cargo carrying container is unrestricted by the gooseneck against lateral shifting.
More specifically, it is known to provide an adjustable adaptor assembly that can be set to “fill” the lateral/widthwise gap between laterally facing tunnel surfaces and the gooseneck. This adaptor assembly must be adjusted to the particular gooseneck and is thereafter fixed in the selected state.
Adjusting the adaptor assembly is inherently inconvenient and may require repeated trial and error to allow proper interaction between the cargo carrying container and chassis. Since the adaptor assembly is fixed in the selected state, it may interfere as the cargo carrying container and chassis are brought together.
The inconvenience associated with using this type of adaptor assembly may be such that operators forego proper setting up of the adaptor assembly. This may lead to an improperly mounted cargo carrying container that could shift, potentially to a dangerous extent, relative to the chassis, in use.
Heretofore, the industry has made containers with a construction dedicated to one or the other of the standard or modified container configurations, as described above. As a result, it is impractical to build up any substantial inventory of such containers given that demand for one style over the other may be unpredictable. Thus, manufacture may proceed only after firm orders are placed, as a result of which delivery may be delayed.
Additionally, by reason of requiring at least two different designs, manufacturing costs may be increased. This is a result of the fact that portions of a manufacturing facility may have to be dedicated to the separate designs. This is detrimental from the standpoint of efficient space utilization. Additionally, different tooling may be required to construct the separate designs. Those assembling separate designs may also be segregated, resulting potentially in an inefficient use of assembly workers.
The above problems have been contended with because the industry has not devised a design that will interface with multiple chassis configurations and that is practical from the standpoint of cost and integrity.